VR6 Cooling questions (Major Breakthrough - Last Page )

[Goldie 2]

Right guys, have searched but still confused here.

 

Jimmi has just fixed my thermostat water leak (ta very ,much Jimmi) and has attempted to sort out my fan speeds as ive only got the one that kicks in at 110.

 

Got the car back and this is the situation:

 

Still only got the 1 fan, would love some suggestions to sort this, have read allsorts of old threads on here and still havent got a clue.

 

Water pump runs on after car shut down if hot, is this normal??

 

Can someone tell me what the 2 fuses are for that are under the bonnet, 1 is a 5A and seems to be linked to the pump and the other is a 20A???

[craigowl 0]

5A is linked to aux pump.

Dont know what 20A is for. Was sound when I looked so did not research what it was for.

[Supercharged 2]

It may be a dead thermoswitch (the one on the rad) if it's only cutting in a 110 - but i'm not too sure about the VR system - worth a try tho...

 

The fuse under the bonnet is either a 30a or maybe a 50a on a VR for the fan controller but this would not work at all without that fuse...

[Goldie 2]

It may be a dead thermoswitch

 

How can i test it??

 

Anyone know what the 20A is for??

[RS VR6 0]

You can always jump the switch.

 

 

The other thing you can check is the connector that plugs into the fan itself. When you unplug it you'll see four connectors. The left and right (large) negative and positive and the upper and lower (smaller) connectors.

 

The upper connector switches on the low speed fan and the lower one switches on the high speed. See if the plastic around the lower connector (high speed) is melted away. I had an issue with a poor connection with the high speed fan connector, that when the high speed fan came on...it actually caused my car to sputter and hesitate. The plastic around the conector was completely melted away. I ended up replacing the entire plug along wth the connectors.

 

 

Not my actual pic...just for reference.

[Goldie 2]

Much appreciated RS VR6, ill check this out and go from there.

 

Anyonew else got any advice /experience??

[Goldie 2]

Ok, heres the state of play now.

 

Tried a different Coolong ECU yesterday to see if this would make speeds 1 and 2 come in and no joy. Next plan is to replace temp sender that is mounted on the passenger side of rad about half way up.

 

Does anyone have any other ideas of what i can try to get these fans running??

 

Other problem i have is no that the thermostat has been replaced my car runs at just under 100 degrees as opposed to 90 while on the motorway. Does this mean the termostat is dodgy, stuck and is there a way to sort it??

 

Thanks in advance, am very determined to sort this once and for al!!

[RS VR6 0]

Heres how to jump the temp switch:

 

by animaniac from VWVortex.

 

"Sounds like a bad fan temp switch which is located in the radiator, this is the only switch which turns the fans on and off.

 

The ignition doesnt feed the fan or the fan temp switch, the fan temp which has a constant 12v live feed, and when the switch senses the correct fan turning on temp it allows the 12v to flow to the low speed and then the high speed.

 

Unplug connector on the rad fan switch and you will see 3 terminals, one will be a 12 volt positive feed and the other to run to the fan.

 

if you bridge the outside terminals the fan will come on either low or high speed, and if the one of the outisde terminals is bridged to the middle terminal the same will happen the fan will come on and will be the opposide fan speed to the other terminal.

 

with the connector on the fan switch unpluged, connect the battery, if the fan doesnt come on then there you have it its a bad fan switch and this is conformed when you plug the fan switch connector back in and the fans come on."

 

To check if your thermostat is opening...when fully warmed up, the lower radiator hose should be hot...if its cold...chances are the t-stat is stuck closed.

[Goldie 2]

Right RS VR6, ill try testing the switch and seeing where i go.

 

Ill check the thermostat tomorrow.

 

Thanks again for the advice.

[Goldie 2]

Still not sorted!!!!!!!!!

 

Have tested all the wiring so only thing left is the temeperature in the rad which i will be getting ASAP.

 

Someone must know something about thermostats, can they be tested??

 

Any tips greatly appreciated.

[bigpants baby 0]

http://volkswagen.msk.ru/index.php?p=page18_cr

[Goldie 2]

bigpants baby, ta very much, some cracking information there.

 

Hopefully i should have this sorted soon.

[RS VR6 0]

To check if your thermostat is opening...when fully warmed up, the lower radiator hose should be hot...if its cold...chances are the t-stat is stuck closed.

 

To check the T-stat out of the car...drop it into a pot of boiling water and see if it opens.

[Goldie 2]

The bottom hose is hot, any more ideas??

[JIMMI 0]

Hi mate

the bottom hose is hot so therefore the thermostat is working fine, have you had chance to replace the temp sender on the radiator?

If the thermostat is opening then i'd guess the new temperature gauge sensor i fitted is sending incorrect readings, i.e the water temp isnt realy what the guage says !

I can get a replacement one from mill and post it down if you like, its a piece of pi$$ to change.

give me a ring or PM if you want

 

Jimmi.......

[Goldie 2]

i.e the water temp isnt realy what the guage says !

 

I did think that JIMMI, but then im still getting the fan at just over 110.

 

Ill give you a shout tomorrow as ive got so much work on today.

[Goldie 2]

Thread Revival Time!!!

 

Situation unchanged - no fans til 110 degrees and car sits at 100 dgrees on motorways and a bit less around the town, say 30 to 50mph.

 

Have had recent new thermostat and radiator temp senser. Think ive got another coolant leak now but only happens everyonce in a while.

 

Please can someone give me an idea firslt why im not getting the fans and secondly why it is running hotter at speed, water pump, radiator??? i feel like im chasing the ace here!!!!

[dr_mat 0]

Sounds like the fan control thermo switch in the radiator is knackered ..

Or, if it's been replaced, you got a DOA.. or the wiring loom to it is knacked .. or the low speed fan fuse has gone (the 110 degree "emergency" fan is on a different fuse).

100 degrees on the water on the motorway is very high, sounds like you have an airlock or a blocked radiator?

Think of it this way - the water in the rad must get hot for the low speed fans to come on, so if the rad is blocked, or the thermostat stays closed, that'll never happen.

 

Beginning to point at the rad. Check it with your hand (gingerly!) when the car is hot - make sure the whole rad is hot (both sides and top-to-bottom). Try bridging the terminals on the radiator temp sensor - make sure the fans come on if the thermo switch .. um.. switches..

[Goldie 2]

The thermoswitch is new. Ill check the wiring loom over the next couple of days. All fuses in the cooling ECU are fine.

 

Am i right in thinking there is only type of stat avilable for my car. Its just i never had the 100 degrees on the motorway until the stat was changed when having a leak sorted. The fan problem has been on the go for a while...

[dr_mat 0]

re: 100 degrees ..

Did they put the stat in the wrong way round ?? You have a screwed thermostat. I had assumed that it was always like that..

 

The thermoswitch could still be faulty, but it's worth doing the checks around it again. Are you sure the low speed fans' fuse is in the cooling block? I think only the high speed fan fuse is in there, could be wrong though. Anyway, if your stat stays closed, no fans come on. That's how it works.

[Goldie 2]

So you reckon i need another thermostat dr_mat??

 

Ill test the thermoswitch, am i right in thinking put a wire across it and the fan should start?

 

Appreciate your assistance...

[dr_mat 0]

Well, if it's true to say that before you changed it the water temps were "normal" 80-90 on the motorway, and after you changed it it's sitting at 100 all day long, then yes, it's screwed.

 

I think that's right on testing the thermoswitch, but perhaps a good idea to figure out which of the connectors is the live and which are the fan feeds with a meter first, I don't have a wiring diagram to hand.

[Goldie 2]

Right, some light on the situation...

 

Had an interesting coversation last night with DanVW at no rice and hes had a similar stat problem.. He replaced his for a VAG supplied one and his temperature went very high. Turns out when comparing the new style stats the dealers are dishing out do not open as far and will cause the engine to run hotter - as mine has been...

 

Intention therefore is to get an old stat that is still ok and put it back in, hopefully thatll get me back down to 90 degrees on the motorway...

 

As for the fans, bridged the lead connecting to the rad switch today and nowt happened, i know that the cooling control module is fine (its from Jimmis car). I know that my fan kicks in at 110 so that motor must be ok so im being pointed towards the wiring between the control block and the thermoswitch.

 

Does anyone know of anything else i should consider, i intend to get a hold of another loom to put in and try but all ideas are welcome..

[double-6s 0]

Hi mate how are ya?

 

Mine was exactly the same. Unfortunately I can't remember what my mechanic fella replaced but it sorted it straight away. And for next to nothing.

 

I'll ring him in the morning and let you no dude :)

 

(sorry - if i had a memory i could help you tonight!! :) )

[Goldie 2]

Im all good thank Will, yourself??

 

Would appreciate that mate, you still have a car your splitting?? Id be interested in getting the wiring and stat if you have..